British investigators have revealed how Argentine soccer player Emiliano Sala and his pilot were exposed to dangerous levels of carbon monoxide before their small plane crashed in the English Channel, killing them both.
Sala's blood showed high levels of carbon monoxide and it was likely pilot Dave Ibbotson had also been exposed before their fatal crash in January.
Sala, 28, was flying from his previous club Nantes in western France to Wales to join Cardiff City when the Piper Malibu aircraft disappeared over the English Channel.
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His body was recovered when the wreckage of the plane was finally discovered about two weeks later.
A special bulletin from Britain's Air Accident Investigation Branch said toxicology tests on his blood had shown that Sala had a saturation level of 58 per cent of carboxyhaemoglobin (COHb), a mixture of carbon monoxide (CO) and haemoglobin.
Carbon monoxide poisoning can lead to damage to the brain, heart and nervous system and a COHb level of over 50 per cent is considered to be potentially fatal, causing seizure, unconsciousness or a heart attack.
"In this type of aircraft, the cockpit is not separated from the cabin and it is considered likely that the pilot would also have been affected to some extent by exposure to CO," the report said.
"It is clear from the symptoms that exposure to CO can reduce or inhibit a pilot's ability to fly an aircraft depending on the level of that exposure."
Sala's family said a detailed examination of the plane wreckage was needed to determine how the gas was able to leak into the cabin.
"That dangerously high levels of carbon monoxide have been found in Emiliano's body raises many questions for the family. How he died will be determined at the inquest in due course," they said in a statement.
"Future air safety rests on knowing as much as possible on this issue."
The AAIB said its investigations were continuing and that a final report would be published in due course.
Widow of pilot says new info a 'massive shock'
Mr Ibbotson, 59, whose body has never been found, may also have succumbed to carbon monoxide poisoning.
Speaking to Sky News, the late pilot's widow Nora said: "This has just come out of the blue. It’s a massive shock. I just didn’t realise that would have happened or could have happened."
"It makes a big difference because they've been poisoned, they have no idea it's a lethal gas.
"You can't smell it. You can't see it. It's lethal, they wouldn't have known.
"So it's nothing to do with the flying or anything like that, it's down to the aircraft.
"I don't know. It's mind-boggling," she added.